The present invention generally relates to tape drives, and more particularly to a simplified tape drive which permits normal advancement of the tape at one speed and rewinding of the tape at a higher speed without the utilization of expensive electrical components or complex mechanical linkage arrangements.
The tape drives for actuating a pair of reels to transfer tape from one reel to the other and for rewinding the tape are already well known. Such tape drives are commonly utilized in various types of audio tape recorders as well as in tape drives for computer applications. However, the prior art tape drives have had serious drawbacks. Firstly, the known tape drives have generally been complex in construction and costly to manufacture. Since most presently used tape drives rely on a capstan-pinch roller arrangement, the tape drives have generally required involved mechanical linkage arrangements for assuring proper engagement between the pinch roller and the capstan. Further, since the tape to be advanced or rewound is disposed between the capstan and the pinch roller, frictional forces are applied to the tape. This has sometimes resulted in damage to the tape. Moreover, mechanical or electro-mechanical means must be provided to disengage the pinch roller from the capstan in the rewind and the fast forward modes.
Most known tape drive mechanisms utilize a uni-directional motor which, necessarily, requires complex mechanical linkages to permit the rewinding of the tape. Such mechanical linkages, in addition to the additional space and weight which they contribute, increase the cost of construction of the tape drive. In this connection, most tape drives of the type under discussion have required, in the prior art, manual operation of the tape drive to cause a realignment of the mechanical linkages to provide the rewind function. For this reason, the tape drives frequently cannot be operated remotely without the utilization of expensive electrical components, such as solenoids.
Also known in the prior art are rim drives wherein a drive wheel frictionally engages the rims of the reels on which the tape is wound. However, except for the elimination of the pinch roller and capstan, the prior art rim drives have suffered the same disadvantages above discussed in connection with the mechanical linkage arrangements for providing the rewind function.
Generally, the prior art constructions have been complex and have not permitted an inexpensive method of controlling the tape drive from a remote location.
Another feature generally considered to be important with respect to tape drives is the availability of different speeds for advancement and rewinding of the tape.
Many prior art tape drives rewind the tape at the same speed as they advance the tape. In some other tape drives, different speeds have been achieved by providing dual motors, one motor being utilized for advancing the tape while the other motor is utilized for rewinding the tape at a different speed. This, clearly, has represented an additional expense which has increased the overall cost of the tape drive.
A further disadvantage of some of the presently known tape drives rests in the fact that these require fly wheels and pulle systems for reducing the speeds of the motor shafts to the desired speeds for rotation of the reels. Fly wheels are also frequently required, when utilizing high speed motors, to stabilize the speed at which the reels advance and to maintain the speed and fluctuations at a minimum. However, fly wheels and pulle systems are generally expensive and space consuming.